This invention relates to a clip for suspending a lighting fixture or other devices from a suspended ceiling.
Suspended ceilings are now in common use. Such ceilings consist of a grid of rails supporting rectangular panels which define the ceiling. Most commonly, the rail is in the form of an inverted T, having a head from which the rail is suspended from a superstructure, a vertical web, and a flat flange base on which the panels rest. Lighting fixtures are either recessed in the plenum above the suspended ceiling or are suspended from the grid. In the latter case, a bracket is clipped onto the base of the T-rail, and a depending hanger part is attached to the fixture.
In U.S. Pat. No. 3,003,735, to Havener, the upper part of a suspension clip twists onto the base of the T-rail. A depending threaded stud is mounted on the clip. Two clips are mounted on either a single T-rail or on adjacent T-rails, in accordance with the desired orientation of the fixture. The fixture is then opened and the studs are extended into knock-out openings in the fixture. A nut is threaded onto each stud from within the fixture, and the fixture is closed. This approach uses several loose parts, requires considerable labor, and is dependent on adequate tightening of the nuts to ensure that the fixture does not work loose.
In U.S. Pat. No. 3,589,660, to Dunckel, a single piece hanger is disclosed. This hanger has an upper part which clips onto the base of the T-rail and a pair of depending wing portions which clip around the entire fixture. This approach avoids the disadvantages of the prior clip, but it introduces other limitations. It requires a massive hanger structure to embrace the fixture, and the size of the wings must be tailored to specific fixtures. Two sets of attachments must be provided on the upper part of the hanger to support the fixture either parallel with or perpendicular to the supporting rail or rails. To provide other, angular, orientations with respect to the supporting rails, the wing portions must be pivoted to the clip portion.
The invention is also directed more generally to clips for supporting objects from suspended ceilings. In many environments it is desirable to support objects such as planters or signs from suspended ceilings. Presently known clips for such purposes are awkward and unsightly.